The invention herein relates to air intakes or exhausts for armored combat vehicles or other structures that are exposed to enemy projectiles such as bullets or shell fragments.
Air intake and exhaust openings are potential points of vulnerability where projectiles can penetrate an armor covering and harm personnel or components inside the covering. Consequently, various means have been developed to protect intake and exhaust openings, the most common protective means being a set of overlapped slats of armor covering these openings. Two problems exist with overlapped slats. One problem is that the slats tend to restrict air flow and another problem is that such slats typically have an identifiable infrared image because they heat and cool faster than neighboring structure.
My invention is an air passage that solves the problem of protecting intake or exhaust openings while reducing air flow restriction and infrared signature. My air passage has ducts with outer open ends at the exterior of an armored structure and other open ends inside the armored structure. The outer ends are grouped adjacently together, and an outwardly flaring bell of armor material is disposed about the group of outer ends, the bell being free of slats or other flow restrictive, high-signature elements. Armor components abutting or integral with the bell form a continuous girdler about the group of outer ends. At the inner ends of the ducts are armor members faced toward the bell and toward the outer ends of the ducts. The ducts define spiralled sections between the inner and outer duct ends, the spiralled sections lying between the bell and the armor members. The juxtaposition of the bell, the ducts and the armor member prevent bullets or like projectiles from entering an armored structure through my air passage.